Please note that FrontPage extensions are only useful if you are using Microsoft Frontpage to build your website.
From the main page in CPanel, click on the Frontpage Extensions link. This can be found under the Advanced header.
Under the Functions tab of this page, click Install Extensions.
This will install FrontPage Extensions for your main domain, but the process needs to be repeated for all of your subdomain or addon domains.
To remove FrontPage extensions for your website, simply return to this page and click Uninstall Extensions.